class Solution:
    def su(self, n):
        A = 65
        re = ""
        while n>0:
            n = n - 1
            r1 = n % 26
            n = n // 26
            re = chr(r1 + A) + re
        return re


s = Solution()
# for n in [1,26,27,28,701,702,703,1000]:
for n in [702]:
    r = s.su(n)
    print(r)
